Calculating device for electrical data, &amp;c.



APPLIGATION FILED NOV. 25, 1907.

Patented June 8, 1909.

PATENT OFFICE.

LOUIS E. GRAVES, OF-LOS ANGELES, CALIFORNIA;

CALCULATIN G DEVICE FOR ELECTRICAL DATA, &c.

Specification of Letters Patent.

Patented .Tune 8, 1909. A

Application iledNovember 25, 1907. Serial No. 403,811.

To all whom it may concern.' .Be it known that I, LOUIS E. GRAVES, acitizen of the United States, residing at Los i ngeles, in the county ofLos Angeles and State of California, have invented a new and usefulCalculating Device for Electrical Data, L-c., of which the following isa specilication.

-The main object of this invention is to provide means for indicating'in a limited space a large amount of correlated data, in such mannerthat any item or series of items may hc quickly ascertained by settingof relatively movable parts. f `v The invention is particularlyapplicable to calculating or ascertaining electrical data relating' tothe properties of wires and consumption devices, such vas are requiredby engineers, contractors, ete., in making plans and estimates forelectrical installations.

Another object of the invention is to provide means for this purposewhich is so compact that it can be carried in the pocket.

ln the accompanying drawing:-Fignre l is a plan of the device. Fig. 2 isa plan of the base sheet or table, the movable indicator being removed.Fig. 3 is a vertical section of the device.

1 designates a base or card of suitable material on which are provided aplurality of series of numbers or marks arranged in concentric circles.A movable disk or member 2 of celluloid cardboard or other material,constituting an indicator, is pivoted at 3 to member 1, for example, bymeans of an eyelet, and covers the inner annular series of marks,leaving one or'more annular series of numbers or marks uncoveredextending around the disk, said disk having an arrow or index 4 thereonto point to the exposed marks, a scale or circular series of divisions'5 being provided on card 1, to facilitate bringing the arrow to theexact point corresponding to any one of the numbers in the outer row orrows. The movable member 2 has openings 6, 7, 8, 9, 10, 11, 12, arrangedin groups, the openings in each group bein at different distances fromthe center of the disk so as to extend over the different series ofnormally covered marks or numbers on the base 1. These groups ofopenings are in different angular portions or sectors 13, 14, 15, 16, 17of the disk, such sectors being appropriated to different classes ofdata.

In applying the device as an electrical calculator, sector 13 hereintermed the main sector of the disk is appropriated to informationrelative to wires, and has openings 6, 7, 8, 9, which are adapted to'eX- pose items relating respectivelypto circular mills, safe carryingcapacity of tWo di'erent classes of wire, and wire-sizes correspondingto different lengths of wire-for carrying different amounts at givenpercentage of drop. The other sectors, 14, 15, 16, 17, herein termed thesupplementary sectors of the disk, taken together are complementary tosector 13 and are appropriated to information relative to amperage ofmotors of different horsepowerthe three openings 10, 11, 12, atdifferent vradial distances in each group corresponding to differentvoltages and the diiferent sectors corresponding to dierent classes ofcurrent (direct, single-phase, ete). The disk is provided with marks 19on its face adjacent to each opening, designating the kind ofinformation to be given thereat.

A segmental portion herein termed the main segment of the outer, exposedseries of numbersl on base 1, comprises two rows, 20, 21, arranged sideby side, and representing respectively horsepower and wire size, and asthe index 4 moves past these numbers in rotation of disk 1, these groupsoccupying a division of t-he base member herein termed the main divisionand said groups; the openings in sector 13 will pass over groups 22, 23,24 in the concentric series of concealed numbers on base 1, representingthe circular mills and safe carrying' capacity of the wires of the sizeindicated by the parts, and the openings in the sectors 14, 15, 16, 17will at the same time pass over groups 25, 26, 27 of marks on thenormally concealed series of -numbers corresponding to the amperage atdifferent voltages for different horsepower, as indicated by the arrow,the row of numbers 21 on the base. Thus a single segment of the exposedparts of the base groups 25, 26, 27, all arranged in a plurality ofdivisions occupying different angular portions of the base member 1 andall herein termed the supplementary divisions of the base member is readwith reference to all the sectors on the disk, by reading the pointerwith reference t'o one or the other of the two rows, 20, 21, extendingin said single segment. This leaves unappropriated a complementar)vsegment to this single segment, which is utilized for other data, beingdivided into groups 29 of numbers arranged in a single row andrepresenting products of with reference to 'V by marks 30. This se withthe given length and given amperage,

will give the drop as indicated in groups 29. These groups 32constituting an extra series of normally concealed marks.

rlhe deviceis used as follows: By setting disk sothat the index 4thereon points to any wire size in row 20, the main segment on the basemember 1 the circular mills for that size can be read at openings 6, inthe main Sector of disk 2 and the safe carrying capacity for dierentclasses of wire can be read at openings 7 and @in the same sector. Or,within the same' range of motion of the disk, by setting the index toany horsepowerl number in row 21, the amperes for that horsepower can beread, for diierent voltages, at the respective openings 10, 11, 12 in'the several supplementary sectors 14, 15, etc., according to the classof current, the horsepower numbers being read in the respectivesupplementary divisions of the numbers on the base member embraced inthe groups 25, 26, 27. Or, `by turning the disk through another range ofmovement, index 4 can be 'made to read with reference to the groups ofnumbers 29, in the supplementary segment of exposed numbers ony the basemember, so that b v multiplying together the amperes to be carried byany wire and the length in feet, and setting the index to the nearestnumber to the product, in the group 29 for the percentage drop allowed,the proper size of wire to use will be shown at opening 9 in the mainsector 13 of the disk. These numbers being read in the specialseries ofgroups of` numbers on the base member which series is of angularextension corresponding to that of supplementary segment 29.

For convenience in carrying, the device is supported v1n a cover havingback and front members 34, 35, to one of which the base card A devicefor the purpose set forth comprising a base member and a disk pivotedthereon, said base member having a main segment comprising two rows ofmarks side by side, and a supplementary segment comprisin a single rowof marks, these two segments Ie ing uncovered by the disk and occupyinga complete circle, said base member having also a plurality ofconcentric oups of marks arranged in divisions in di erent angularpositions and normally coveredby the disk and said disk being alsoprovided with an extra series of normally covered marks corresponding inlength to the supplementary segment of uncovered marks, and a diskhaving an index for indicating the position of the disk with referenceto the uncovered series of marks, said disk being provided with 'aplurality of openings in a main sector thereof to expose for reading themarks in the main division on the base member when the index reads onone of the rows of marks in the main uncovered segment on the basemember and said disk having'openings in a ,plurality of supplementarysectors thereof for expos ing the marks in each of several dierentsupplementary divisions of groups of marks on the base member when theAindex reads with reference to the other row of marks in the mainuncovered segment on the base member, and said disk having in the mainsector thereof an opening for reading in theextra series of normallyconcealed marks onv the base when the index reads with reference to thesupplementary segment of uncovered marks 011 the base member.

. In testimony whereof, I have hereunto set my hand at Los `Angeles,California, this 18th day of November, 1907.

LOUIS E.' GRAVES. In presence of- ARTHUR P. KNIGHT, FRANKV L. A. GRAHAM.

